Apparatus for mounting carrier arms in spinning machines

ABSTRACT

The top roller carrier for spinning yarn is mounted within a support and a lever is pivoted at one end to the support. The carrier is pivoted at a first point to the lever, and at a second point to the support. The lever is adapted to raise and lower the arm so that the pivot points move in arcuate paths, into closed and open positions.

United States Patent [191 Brichta et a1.

[451 June 26, 1973 APPARATUS FOR MOUNTING CARRIER ARMS IN SPINNINGMACHINES [75] Inventors: Franz Brichta, Stuttgart-Weilimdorf; FranzDriesel, Oberweissach, both of Germany [73] Assignee: SKFKugellagerfabriken GmbH,

Schweinfurt, Germany [22] Filed: Mar. 8, 1971 [21] Appl. No.: 121,719

[30] Foreign Application Priority Data Mar. 12, 1970 Germany P 20 11641.0

[52] US. Cl. 19/267, 19/295 [51] Int. Cl D0111 5/46 [58] Field of Search19/266, 267, 268, 19/272, 295

[56] References Cited UNITED STATES PATENTS 2,958,103 11/1960 Schrotz19/266 FOREIGN PATENTS OR APPLICATIONS 923,549 4/1963 Great Britain19/295 Primary Examiner-Dorsey Newton Attorney-Richard Low and MurraySchaffer [5 7] ABSTRACT The top roller carrier for spinning yarn ismounted withina support and a lever is pivoted at one end to thesupport. The carrier is pivoted at a first point to the lever, and at asecond point to the support. The lever is adapted to raise and lower thearm so that the pivot points move in arcuate paths, into closed and openpositions.

10 Claims, 8 Drawing Figures PA ENIED 3. 740. 798

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IN VEN TORfj APPARATUS FOR MOUNTING CARRIER ARMS IN SPINNING MACHINESBACKGROUND OF INVENTION The present invention relates to apparatus formounting carriers of top rollers in the drawing mechanism of a spinningmachine.

Carrier arms of conventional drawing mechanisms are shown in German Pat.No. 1,088,850 and U. S. Pat. No. 3,212,139 to which reference can bemade. In such devices a carrier arm is arranged with a plurality ofsupports mounting at their ends top rollers which are adapted to engagerespective associated bottom rollers to form the drawing plane fortwisting of sliver fibers. The carrier arm extends with a rectangularopen or U- shaped housing support and is pivoted about a pin secured ina straight slot formed in the latter walls of the housing support. Thecarrier arm is linked to an operating lever which has its end mountedabout a pin located in the housing support above that of the carrierarm. The lever is guided, however, in an arcuate slot so that it may beraised and lowered to carry with it the carrier arm. The shape andinclination of the two slots must be chosen so that when the lever andcarrier are unlocked or opened the upward movement of lever and carrierarm does not cause the top rollers to roll or have a translatorymovement relative to the associated rollers. This is necessary tominimize disturbance of the sliver fibers located therebetween.Simultaneously, however, the forwardmost top roller (in the direction offiber movement) must initially remain in contact with its roller, sothat the already spun fibers are not prematurely released and the twistlost. On closing the mechanism, i.e. on downward movement of the leverand carrier arm, the upper rollers must first rest without pressure onthe lower rollers for the same reasons. The actual loading or locking ofthe carrier arm in operative position must thereafter be accomplished byforcibly depressing the lever. Under the high loading forces currentlyemployed for special fibers this last step requires substantial force. Adisadvantage of this conventional construction lies in the fact that thegeometrical construction, the upward movement of the lever and of thecarrier superinposes a certain arcuate movement on a certain translatorymovement. Another disadvantage is that the construction is not whollysuccessful in obtaining the relative motions between the rollersrequired for good operation. Furthermore, the forces required to insureperfect locking are considerable and often hinder smooth operation. I

It is the object of the present invention to provide apparatus formounting carrier arms which overcome the problems of the prior art.

It is another object of the present inventionto provide apparatus'formounting carrier arms which do not require excessive force for theirclosing and which may be more securely guided during its movement. Inparticular, it is an object to provide an over-the-center linkage systemwhich insures proper closing operation.

It is another object of the present invention to provide apparatus formounting carrier arms in which the carrier arm may be moved as anintegral part of a linkage system and wherein a particular point on thecarrier arm may be employed to define the required path of travel.

It is yet another object to provide apparatus for mounting carrier armsin which means are provided for the partial opening of the drawingmechanism and which also provides means for locking the carrier arm andlever in open position.

These objects, numerous others, as well as numerous advantages will beobvious from the following description.

SUMMARY OF INVENTION According to the present invention apparatus formounting carrier arms of a drawing mechanism for a spinning machine isprovided which comprises a fixed support housing in which the ends ofthe carrier arm and operating lever is mounted. The lever is pivotallysecured to the housing about a fixed pin while the carrier arm ispivoted at one point to the lever and at another to the housing so as toprovide an arcuate path of travel for the pivot points on raising orlowering of the lever.

Preferably the pivot points are arranged in an array in which the pivotlink between the carrier and the lever is offset slightly below thepivot pin of the lever and the support and the two pivot points of thecarrier arm are located on opposite sides of a line passing through thecenters of the arcuate paths.

Further, it is preferred that the carrier comprise a link in a four barlinkage system so that the point of travel of a given top roller isdefined.

Various other features such as an over-the-center linkage system, and alocking system are provided.

Full details of the present invention follow herein and can be seen fromthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings:

FIG. 1 is a side elevation view of a drawing mechanism, in closedposition,

FIG. 2 is a view of the mechanism in partially loaded or open position,

FIG. 3 is a side section in enlarged form of the carrier arm and supportshown in FIG. 1, I

FIG. 4 is a sectional view taken along line 4--4 of FIG. 3,

FIG. 5 is a view similar to FIG. 3 showing the mechanism in partial openposition, as in FIG. 2,

FIG. 6 is a view of the mechanism fully opened and in locked position,and

FIGS. 7 and 8 are sectional views taken along line 77 of FIG. 6 showingthe locking arrangement in closed and open positions respectively.

DESCRIPTION OF INVENTION FIG. 1 shows a stationary housing support 10which is normally fixed to the machine frame. A holding rod 12 extendsthrough the housing 10 and holds a multiplicity of carrier arms 18 onwhich are arranged the rollers of a drawing mechanism of aspin'ningmachine. Each carrier arm 18 is mounted separately. A pin 14 is mountedin housing 10 and holds an operating lever 16 for each carrier arm 18.The end of the carrier arm 18 (to the right in FIG. 1) is also receivedand supported in the housing 10, and has depending walls 18.

The carrier 18 supports a plurality of top roller supporting mounts 20,22 and 24. Each supporting mount has a link 28, 30 and 32 respectivelypivoted counterclockwise about a pin 26. The links each have a saddle inwhich the top roller is resiliently held by a spring (FIG. 3). Apreferred structure for the top roller supports is shown andfullydescribed in co-pending application of the assignee hereto of FranzFuchs, Ser. No. 120,535 based upon German application P 20 104.6 filedMar. 4, l970, to which reference for details can be made.

Each top roller is opposed by a bottom roller 40, 42 and 44respectively, which are themselves rotatably journalled in a stationaryarm 46. In this form the drawing mechanism appears as a conventionalthree roller device (in which belts may be incorporated) defining acommon tangential plane between the rollers through which fibers,slivers or the like are moved in the direction of arrow A and spun inconventional manner.

The structural details of the carrier supporting assembly can be seen inFIG. 3. In this figure the rear end only of the lever 16 and uppercarrier 18 is shown and the rearmost support arm 20 and associatedrollers 34 and 40 are indicated in dotted lines. It will be obvious thatboth the lever 16 and the carrier arm 18 are of reverse U-shaped crosssection. The carrier arm 18 is pivotally mounted at its upper end abouta pin 50 which is secured in the lever 16 and at its lower end by meansof a second pin 52 to a pair of arcuate levers 54 which itself ispivotally secured at its arcuate other end to the support housing 10 bymeans of a fixed bolt 56. As will be seen from FIGS. 4 and 8, the entireapparatus is symmetrical to a median plane and the two lugs 54 areidentical, being joined at their ends by sleeve 58 and sleeve 60 locatedabout the pins 56 and 52 respectively.

The levers 54 are shaped in such a manner that they rest on thesupporting rod 12 when the carrier arm 18 is placed in the operatingposition, as illustrated in FIG. 3.

Furthermore, two leaf springs 62 are fastened at one end about the pivot50 of the carrier arm 18. The free ends of the leaf springs 62 carrylaterally extending pins 64. In the lateral walls 18' (FIG. 4) of thecarrier arm there are provided openings 66 through which each of thepins 64 are adapted to seat. The pins 64 and springs 62 move with thecarrier arm. The pins 64 are normally biased to ride against the innersurface of the support 10 under the action of the leaf springs 62 whenthe carrier is in the operation position (FIG. 3) and when the carrieris moved through all other positions with the exception of the upperterminal or locked position when it seats with a hole 80 bored into thewall of housing 10 as will be hereinafter described. The leaf springsare freely mounted on the pin 50 and are separated by a sleeve 68surrounding the pin.

As is illustrated, in FIG. 3, an approximately S- shaped flexibletorsion leaf spring 72 is attached to the rear wall of the housing 10 bymeans of two rivets 70. The spring 72 extends into contact andcooperates with the pin 52 or its sleeve 60 to resiliently load thelinkages connecting the pivots 14, 50, 52 and 56 when the lever 16 isinitially partially-pivoted as will hereinafter be explained so that thecarrier arm is predisposed into its closed and operating position.

When the operating lever 16 is initially pivoted by means of the handle48 from the positions shown in FIGS. 1 and 3, the pins 50 and 52 areguided along circular arcs which initially cause the top rollers 34 and36 to be lifted from the lower rollers 40 and 42 (FIG. 2). The mechanismthus assumes a partially loaded (partially unloaded) position where onlythe top roller 38 continues to rest upon its associated lower roller 44.Simultaneously the carrier arm 18 is shifted in the direction of arrow A(FIG. 1) through the action of the four bar system defined by the pivotpoints 14, 50, 52 and 56 and their connecting elements. The connectingelements are so dimensioned that the pivoting component of the toproller 38 about its pivot pin 26 in a direction opposite to the arrow A(FIG. 1) is nil during this initial stage and is compensated for so thatthe point of contact between the top roller 38 and its associated lowerroller 44 is not moved. This condition exists until the partial unloadposition of the rollers 32 and 34 is reached, as illustrated in FIGS. 2and 5.

When the operating lever 16 is pivoted upward from the position shown inFIGS. 1 and 3 to the position shown in FIGS. 2 and 5, the pins 50 and 52are caused to move along a circular path the center of which lies remotefrom the pins and in the direction of the top and bottom rollers of thedrawing mechanism. The radius of the arcuate path is relatively largealthough the circular motion is evident even with the small movementsrequired. On initial operation the pin 52 and its sleeve 60 are causedto abut against the torsion spring 72, as best seen in FIG. 5. Bychosing the rate of torsion spring 72 at a predefined level so that onits contact with the pin 52 and its sleeve 60 the torque exerted by itis balanced with the torque exerted by the spring which biases theroller 38, the initial partial loading position described above andshown in FIG. 5, can be readily defined and determined. Generally, thedrawing mechanism is arranged so that during drawing operation the toprollers 32, 34 and 38 rest upon their associated rollers with a forceapproximating 30 K,,. In the partial load position, however, the roller38 is caused to rest on the roller 44 with a force of only 5 K thisbeing obtained by balancing the torques of the springs and the linkagesystem described. A partial loading position is necessary in order toprevent the deformation of the roller bodies when the operation of themechanism is temporarily stopped. Otherwise the large static pressure ofthe rollers against each other would distort their circular crosssection. At the same time a partial loading is required at least for oneroller, in order to hold the fiber sliver in place and to prevent runthrough of the fiber and to avoid the loss of the twist.

When the operating lever 16 is thereafter pivoted still further upwardly(clockwise) the pin 52 is further arcuately pivoted to displace thetorsion spring 72 toward its fixed side. The roller 38 is then liftedcompletely from contact with its lower roller 44. Simultaneously, thepins 64 which normally ride within holes 66 come within range of theopenings formed in the lateral walls of the housing 10. Finally, as theholes 66 align with the openings 80 the pins 64 pass into the openings80 and thereby lock and hold the lever 16 and carrier arm 18 in openposition, as shown in FIGS. 6 and 7.

The device is released from locked position by the downward movement ofthe operating. lever 16. This last figure (FIG. 7) also shows that thepin 50 passes through an elongated slot 82 in the operating lever 16which is also shown in FIG. 3. This arrangement provides sufficient lostmotion between the carrier and the lever so that even on continuedupward movement of the lever, beyond the locking position, the lock isnot released and the carrier is not moved either. The locking mechanismthus functions automatically when holes 66 and 80 are aligned. The twoleaf springs 62 are offset below their points of attachment with the pin50, forming a shoulder or bend 84. This prevents the car rier arm 18from being moved during the initial portion of the downward movement ofthe operating lever 16 and the pins 64 remain in holes 80. The lowermarginal areas or edges 86 of the lever 16, seen in FIGS. 7 and 8, serveas unlocking elements for the leaf springs 62. The edges 86 engage withthe shoulders 84 of the leaf springs and with the application of a smalldegree of force cause the springs to recede and remove the pins 64 fromthe holes 80. Thereafter, on application of continued force, the carrierarm 18 and the lever 16 can be moved downwardly from the position ofFIG. 6 to that of FIG. 3 and until the top rollers abut against thelower rollers so that the forces of reaction of the latter exert atorque on the pin 50 relative to the pin 14 in a counter-clockwisedirection. This torque is exerted when the pin 50, the longitudinal axisof carrier arm and the pivot pin 14 are aligned so that a straight lineruns in a downwardly direction substantially through the center of each.At this point the reaction forces of the lower rollers 40 44automatically exert sufficient pressure to close the lever and carrierarm so that the upper rollers are pressed against the lower rollersuntil the arcuate levers 54 abut against the holding shaft 12. Duringthe downward movement the pin 52 deflects the torsion spring 72 to theright because of its doubly curved form.

As will be seen from an analysis of the geometry of the disclosedmechanism that in the closed or operating position the two pivot points50 and 52 be located on opposite sides of a connecting line A betweenthe centers l4 and 56 respectively of two arcuate paths B and C in whichthey travel and that the upper pivot 50 is offset from and is locatedonly slightly below or adjacent a line D passing through the pivot point14 connecting the operating lever, and parallel to the elongation of thecarrier arm. It is also to be seen that the lower pivot point 52 islocated approximately on a line E which runs parallel to the directionof elongation of the carrier arm and through the center of its arcuatepath. Thus the carrier arm 18 constitutes an element of a four barlinkage system which precisely defines a path of predetermined directionfor a point on the carrier arm. By suitable arrangement this conditioncan be obtained, for example, with respect to the center of the rearmosttop roller 34 the arrangement can be constructed so that the roller 34is lifted from the bottom roller 40 without any rolling or translatorymovement.

It will thus be seen that the carrier arm is mounted to pivot about twopoints, both of which are located on the bottom of the carrier arm orfacing the top rollers and both of which move in their own arcuate orcircular paths. An advantage of this construction is that very smallforces are required to pivot the carrier arm into and out of operatingposition.

By arranging the first of the pivot points 50 as the connecting linkbetween it and the operating lever special buide elements and complexconstructions are avoided. By spacing this pivot point from the pivotaxis 14 of the operating lever the magnitude of the compensatingmovement of the carrier arm may then be determined in a simple manner,provided that the pivot point does not shift radially of the circularpath. This also prevents the axial translation, or rolling of the topand lower rollers with respect to each other, on lifting of the carrierarm.

The arcuate lever 54 by which the second carrier arm pivot point 52 isguided also has great advantage. The

abutment of this member against the necessary holding rod 12 provides asimple stop mechanism. It will be appreciated, however, that the lever54 can be replaced by a pin or key arm extending from the end of thecarrier arm, which pin or arm could ride within a slot or keyway ofarcuate shape formed or mounted on the housing wall. The same may bemounted directly on the holding rod. The described linkage system hasstill another advantage, in that it provides a so-called overthe-centercrank by which it is possible to pass through a particular point in thepath of movement, after which the carrier arm becomes automaticallyclosable by the operation of the forces of reaction of the lowerrollers. This insures that the carrier arm will securely close when theoperating lever is depressed for this intention. To this end it is alsohelpful that the two pivot points are located on opposite sides of aline passing through their arcuate path centers and to locate the pivotconnection of the carrier arm with the operating lever only slightlybelow a line through the pivot point of the operating lever and parallelto the elongation of the arm. This supplies the necessary arrangement sothat the over-the-center point is associated with a position of theoperating lever in which the latter forms only a relatively small anglewith the carrier arm. Simultaneously, a relatively large compensatingmovement of the carrier arm is obtained.

The present arrangement also provides a simple arrangement for obtaininga partial loading position. This is achieved by locating the pivot point52 approximately in or'c'ontiguously adjacent a line parallel to thecarrier arm and passing through the center of its arcuate path. A greatdifference in the lifting of the rear and of the frontmost upper rollersis obtained (i.e. the rearmost portion of the carrier passes through agreater movement or distance). It is to be understood, however, that thepivot point 50 of the carrier arm must not be located below the pivotaxis of the point 14 of the lever 18. The S-shaped spring 72 insuresthat the forward most roller 38 maintain contact with the associatedroller 44 to hold the yarn. By its pressing against the pivot point 52the spring 72 urges the carrier arm always into closed position.

The jointly movable leaf springs 62 with pins 64 provide a very simpleand effective locking means.

It is thus seen that the present structure is very simple, it does notrequire excessive expensive parts and may be easily constructed. Variousmodifications have been indicated. Others will be obvious to thoseskilled in this art.lt is therefore, intended that the presentdescription be taken as being illustrative only.

What is claimed is:

1. Apparatus for mounting the top roller carriers of a drawing mechanismfor a spinning machine comprismg a fixed support housing,

an operating lever pivoted at one end to said housing, a carrier armhaving one end mounted with said housing and having a plurality of toprollers arranged along its length,

means for pivotally connecting said one end of said carrier arm at afirst pivot point to said operating lever, and movable means for linkingsaid one end of said carrier arm at a second pivot point to saidhousing, said pivot points being movable in arcuate paths on pivoting ofsaid operating lever whereby said carrier arm is caused to be lowered orraised into a closed operating position and in open nonoperatingposition respectively.

2. The apparatus according to claim 1 wherein said linking meanscomprises an arcuate lever secured at one end to said second pivot pointand at the other end to said housing.

3. The apparatus according to claim 1 wherein in the operating positionthe two pivot points are located on opposite sides of a connecting linebetween the centers of the two arcuate paths and the first pivot pointis located only slightly below a line passing through the point at whichthe operating lever and housing are pivoted and parallel to theelongation of the carrier arm.

4. The apparatus according to claim 3 wherein the second pivot point ofcarrier arm is located in the operating position approximately on a linewhich runs parallel to the direction of elongation of the carrier armand through the center of the arcuate path of said second pivot point.

5. The apparatus according to claim 1 including pivot means at saidsecond point comprising a pin, and including resilient means adapted toengage said pin on its upward movement and bias said carrier arm intoits 8 operating position.

6. The apparatus according to claim 5 wherein said resilient meanscomprises an S-shape leaf spring secured to said support housing.

7. The apparatus according to claim 1 including means for locking saidlever and said carrier arm in open non-operating position.

8. The apparatus according to claim 7 wherein said locking meanscomprises a spring having a lateral pin adapted to ride within a hole insaid carrier arm, a hole in said support housing, said hole beingarranged in alignment in the open non-operating position and said pinbeing adapted to enter and seat in said hole.

9. The apparatus according to claim 8 wherein means are provided on saidoperating lever for engaging said locking spring on the downwardmovement thereof to flex said spring and release said pin from said holein said support housing.

10. The apparatus according to claim 1 including a lost motion linkageconnecting said carrier arm and said operating lever to permit the leverto move through a predefined distance without moving the carrierarm.

1. Apparatus for mounting the top roller carriers of a drawing mechanismfor a spinning machine comprising a fixed support housing, an operatinglever pivoted at one end to said housing, a carrier arm having one endmounted with said housing and having a plurality of top rollers arrangedalong its length, means for pivotally connecting said one end of saidcarrier arm at a first pivot point to said operating lever, and movablemeans for linking said one end of said carrier arm at a second pivotpoint to said housing, said pivot points being movable in arcuate pathson pivoting of said operating lever whereby said carrier arm is causedto be lowered or raised into a closed operating position and in opennon-operating position respectively.
 2. The apparatus according to claim1 wherein said linking means comprises an arcuate lever secured at oneend to said second pivot point and at the other end to said housing. 3.The apparatus according to claim 1 wherein in the operating position thetwo pivot points are located on opposite sides of a connecting linebetween the centers of the two arcuate paths and the first pivot pointis located only slightly below a line passing through the point at whichthe operating lever and housing are pivoted and parallel to theelongation of the carrier arm.
 4. The apparatus according to claim 3wherein the second pivot point of carrier arm is located in theoperating position approximately on a line which runs parallel to thedirection of elongation of the carrier arm and through the center of thearcuate path of said second pivot point.
 5. The apparatus according toclaim 1 including pivot means at said second point comprising a pin, andincluding resilient means adapted to engage said pin on its upwardmovement and bias said carrier arm into its operating position.
 6. Theapparatus according to claim 5 wherein said resilient means comprises anS-shape leaf spring secured to said support housing.
 7. The apparatusaccording to claim 1 including means for locking said lever and saidcarrier arm in open non-operating position.
 8. The apparatus accordingto claim 7 wherein said locking means comprises a spring having alateral pin adapted to ride within a hole in said carrier arm, a hole insaid support housing, said hole being arranged in alignment in the opennon-operating position and said pin being adapted to enter and seat insaid hole.
 9. The apparatus according to claim 8 wherein means areprovided on said operating lever for engaging said locking spring on thedownward movement thereof to flex said spring and release said pin fromsaid hole in said support housing.
 10. The apparatus according to claim1 including a lost motion linkage connecting said carrier arm and saidoperating lever to permit the lever to move through a predefineddistance without moving the carrier arm.